The present invention is directed to a process for forming a barrier structure useful in the construction industry. More specifically, the presently disclosed process forms an insulation/waterproofing barrier or in another embodiment, a water drainage enhancer/waterproofing barrier in a simple one step application.
Built up roofing has been employed for many years wherein a roof deck supports a membrane which prevents penetration of moisture. Such water impermeable membranes have been formed from conventional asphaltic and bituminous compositions, laminates of the asphaltic or bituminous material with fibrous products, such as roofing felt or from rubberized asphalt, synthetic polymeric compositions or by applying sheet waterproofing membranes such as formed from butyl, neoprene or a polymer film supported rubberized asphalt. Such materials are generally applied by mopping, etc., of multiple layers of the waterproofing material until a thick weather-resistant membrane is formed. Gravel or the like is normally used to cover the membrane to enhance its weathering ability. Further, the roof structure normally contains insulation to aid in maintaining constant and comfortable temperature within the structure. The insulation is conventionally installed below the roof deck on the interior of the building.
More recently, it has been found that installation of insulation on top of the exterior surface of the roof membrane has the advantages of maintaining the applied waterproofing membrane at a more constant temperature causing longer life of the membrane. Such roofing structures has been dubbed "upside down roofs". The conventional manner of forming an upside down roof entails first applying a waterproof roofing membrane, such as formed from asphalt or butuminous composition, allowing the applied composition to cool and permitting sufficient time for the asphalt to cure by the evaporation of volitiles. A mastic is then applied to the membrane by spraying or the like to cause adhesion and anchoring of the subsequently applied insulation. A protective layer is applied over the insulation and, finally, gravel or the like material is applied on top to further aid in anchoring and securing the structure.
Conventional asphaltic waterproofing membrane materials are not generally used in the installation of upside-down roof structures. Such membranes are weak, tender materials which are required to be in contact with a support sheet, such as a polyethylene sheet, to enhance the strength of the membrane and to protect it from puncture and the like damage. Such support sheets must be securely adhered to the membrane and, therefore, cannot be removed without tearing and destroying the sheet material. The support sheet, however, inhibits adhesion of any subsequent layer, such as that of a porous insulating material and the installer must, therefore, apply a strong mastic and an anchoring cover, such as gravel, etc., over the insulation material to maintain its position.
The upside-down roof structure has not met extensive acceptance in the industry even though it has the advantage of enhancing the durability and life of the waterproofing membrane by shielding the membrane from the environmental temperature changes it normally encounters. The lack of acceptance is mainly due to the extensive time required for installation, the care required by the installers, the various materials required at the job sight and the extensive amount of man hours required to produce the formation.
Barrier protection is also used on vertical surfaces, such as foundation walls, by parging the foundation's exterior surface with a waterproofing paint or cement or an asphaltic composition. This must be carefully done to assure that it fully covers the foundation surface and does not leave gaps which would permit water seepage through the foundation wall. When drainage enhancement is desired, this is normally accomplished by placing drainage tile or pipe at the foundation footing and installing gravel or the like over the tile and against the parged foundation wall during backfill. Formation of such a barrier is labor intensive, requires use of heavy material and, therefore, heavy equipment, and the installation of the gravel tends to chip and break the formed waterproofing membrane.
It is desired to have a process and a material capable of forming a thermal/moisture barrier which can be applied with minimum amount of labor and time. It is also desired to have a process and a material capable of forming a drainage/moisture enhancing means which can be easily applied with minimum amount of labor and time.